CUT-GRASS SMELL POLLUTING AIR

Mark Welterlen MWELTERLEN@PRIMEDIABUSINESS.COM

Open the window this time of year and you're bound to notice the lovely smell of freshly cut grass. But is it so lovely? Not according to researchers in Australia. They contend that the gas omissions from freshly cut grass is an overlooked pollutant that is a significant contributor to urban smog.

Earlier work in 2001 by Austrian researchers determined that the aroma we detect from freshly mown grass primarily comes from six-carbon hexenyl compounds (hexenyl acetates, hexanals, hexenols and saturated C6 hexenal) in addition to acetaldehyde, acetone, methanol, ethanol, butanol and butanone. The Austrian researchers also found enhanced emission of acetone from drying grass after a rain.

Armed with this information, the Australian researchers point out that the hexenyl emissions from cut grasses are highly reactive, are potent precursors of ozone and in urban areas will contribute to the formation of photochemical smog. With so much suburban acreage in turf and in close proximity to cities, the obvious link to urban smog formation is evident. So much for suburban-bashing. Pretty soon we are going to hear that barbeque grills contribute to smog too. (Or have we already?)

Kirstine, W., I. Galbally and M. Hooper. 2002. Air pollution and the smell of cut grass, 16th International Clean Air Conference, Christchurch, New Zealand, August 2002.